Some vehicles, such as rail vehicles, may undergo tunneling operation in which the vehicle travels through a confined space, such as a tunnel. During tunneling operation, temperatures of various systems of the vehicle such as an engine system and a cooling system, may increase. In some examples, the temperatures may increase substantially, leading to decreased power and overheating of the engine of the rail vehicle.
In one approach, heat rejection to the cooling system and tunnel may be reduced by adjusting an operating parameter such as engine exhaust gas recirculation (EGR) in response to an indication of tunneling operation based on ambient temperature, turbo inlet temperature, or engine oil temperature. As an example, an engine EGR amount may be substantially or completely reduced. In such an approach, however, the operating parameter may not be adjusted until the engine is far enough inside the tunnel for temperatures of various systems to have already increased. Further, if an engine EGR amount is completely reduced, emissions compliance may be compromised.